1. Field of the Invention
The present invention relates to a bowling ball having an internal weight whose position is adjustable by a remote controller for altering the path of the ball after it is released by the player.
2. Description of the Prior Art
The conventional way of using a bowling ball is to roll it over the surface of a bowling alley in a direction best calculated to knock over the bowling pins at the far end of the alley. A player has no control over the path of the ball once it is released.
The path of travel of the ball can initially be controlled to a certain extent by the spin or hook a player imparts to the ball on release. Beyond the release point there is nothing a player can do to correct the path of an errant ball, much as the player would like otherwise.
In U.S. Pat. No. 5,058,901 (Salvino) issued Oct. 22, 1981 the inventor observed that when weight is drilled or otherwise removed from the ball to provide thumb and finger holes, the path of the ball was adversely affected by the resulting change in the center of gravity of the ball. According to the patent, this dynamically unbalanced condition could be corrected by locating a rod along the spin axis of the ball. The consequent increase in weight along that axis was designed to reduce the tendency of the ball to wobble after it was released. The axial position of the rod was adjustable between each use to some position that the player felt would be most likely to establish the best path for the ball as it rolled down the alley. It is likely that precise placement of the rod was not easy to achieve since most players xe2x80x9chookxe2x80x9d a ball to a varying extent during play and this, together with other variables such as the state of the bowling alley surface, would make it difficult to consistently reach a predictable result. In any event, the arrangement did not provide any dynamic control of the ball. The system amounted to a trial and error procedure in which a player was always trying to match his bowling results with various fixed positions of a rod in the ball. It was not possible to control the path of the ball after it was released.
U.S. Pat. No. 3,591,177 (Skuse) discloses an invention generally similar to the ""901 patent just discussed except that a threaded rod was used. Its axial position was adjusted by rotating it along a threaded bore using a screw driver inserted into an access opening from the exterior of the ball. However, during play the position of the rod was fixed. Dynamic adjustment was neither taught nor suggested as being desirable.
A somewhat related arrangement is shown in U.S. Pat. No. 4,058,310 (Miettinen), except that he uses mercury to alter the location of the ball""s center of gravity. The mercury is located in one of three elongated chambers that extend radially outwardly from the center of the ball. One or the other of these chambers is filled with the mercury through a three-way valve whose rotated position is changed when a chamber is filled with the desired amount of mercury. The stem of the valve extends outwardly from the center of the ball, and is turned by a key that is inserted through the exterior surface of the ball. The key thus controls which chamber is filled, and to what extent. However, like the other patents discussed above, the position of the valve and other adjustable components are fixed and cannot be changed once the ball has been released for travel down the alley. No dynamic control of the ball path is possible.
A system is disclosed in U.S. Pat. No. 4,501,569 (Clark Jr. et al) for remotely and dynamically controlling the location of the center of gravity of a spherical vehicle. The mechanism includes an elongated axle which extends diametrically along the spin axis of the sphere. The ends of the axle are fixed within the sphere, and a frame which supports the axle is rotatable about the transverse or spin axis of the sphere. An axle gear is fixed to the axle and engaged by a pinion gear. The pinion gear is rotatable by the drive shaft of a motor that is attached to the frame. As a consequence, rotation of the pinion gear rotates the motor and frame about the axle.
Attached to the frame is the inner end of a radially extending pendulum arm whose outer end carries a mass or weight. The frame includes an integral arcuate gear rack that is engaged by the pinion gear of a servo motor which, like the weight, is mounted to the pendulum arm. Rotation of the servo motor thus causes the arcuate gear segment and weight to rotate to one side or the other of the spin axis along which the axle extends.
The servo motor is operable by a remotely located radio transmitter whereby adjustment of the location of the center of gravity of the mass is done dynamically.
A similar result is achieved by the system of U.S. Pat. No. 4,726,800(Kobayashi). A spherical toy includes a center-shaft extending along the spin axis of the toy. The system is controlled by a remotely located radio transmitter that operates a radio receiver within the toy. The receiver operates a battery to energize a servo motor whose output or drive shaft is coupled to a relatively complex connecting structure. This structure is operative to move a direction control means to one side or the other of an axis generally perpendicular to the spin axis of the toy. Such movement adjusts the location of the center of gravity of the toy for dynamically adjusting the path of the toy as it rotates on its spin axis. Although the path axis of the toy is controll remotely by radio signals from a radio transmitter, the structure which uses these control signals to relocate the center of gravity is complex and consequently expensive and time consuming to manufacture and maintain.
In my copending patent application Ser. No. 09/828,605, the direction or path axis of a bowling ball is dynamically adjusted as it travels down a bowling alley by moving an internal weight along the spin axis of the ball. This adjusts the location of the center of gravity of the ball and thus the path of the ball. The internally threaded weight is prevented from rotating about the externally threaded weight shaft, but the weight shaft is rotatable so that it can threadably move the weight along the shaft axis. A disclosure of this system is included in the present application to facilitate understanding of the structural differences between such a system and the system of the present invention, and particularly the utilization in this system of a weight shaft that is fixed against rotation.
Thus, according to the present invention the weight shaft is non-rotatable. In one embodiment the motor is made integral with the weight and both are axially slidable upon interior walls of the bowling ball. However, they are constrained against rotation by their engagement with the walls.
A motor gear on the output shaft of the motor rotates a drive gear which is frictionally engaged with a threaded nut sleeve. The nut sleeve is threadably carried by the weight shaft and is rotatably supported within the weight by rotatable bearings. When the friction between the nut sleeve and the drive gear is sufficiently great, rotation of the drive gear rotates the nut sleeve such that the nut sleeve rotates and threadably advances the nut sleeve and the weight along the length of the non-rotatable weight shaft, thereby adjusting the center of gravity of the ball. However, when such friction is low, the nut sleeve will slip and not be rotated by the drive gear. Adjustment of the degree of frictional engagement is provided by a clutch spring washer that is disposed between the drive gear and the nut sleeve.
This function of the clutch spring washer is useful if the nut sleeve has been rotated in one direction or the other along the length of the weight shaft to an end stop on the shaft. The torque of the drive gear then becomes insufficient to rotate the nut sleeve, and the clutch spring washer then slips, thereby preventing damage which might occur if the nut sleeve could not slip and is forcibly urged against the fixed end stop.
In another embodiment of the present system the motor is a standard rotor-stator motor in which the stator is integral with the weight and both the stator and the weight are constrained against rotation by engagement of the weight with the interior walls of the bowling ball, but are axially slidable over the walls. The rotor is fixed to a nut sleeve which is threaded onto the weight shaft. When the stator is energized, it cannot rotate but the rotor and nut sleeve are rotatable about the fixed weight so that the nut sleeve can move axially along the length of the weight shaft to adjust the center of gravity of the ball.
In certain situations use of those embodiments which include a fixed weight shaft is advantageous compared to the embodiments disclosed in my copending patent application which employ a rotatable weight shaft.
Other objects and features of the present invention will become apparent from the following more detailed description taken in conjunction with the accompanying drawings.